The invention relates to a process to seal structural joints with the aid of an injection hose comprising a substantially liquid-impermeable base body which defines a passage channel and which has exit openings distributed over the length of the base body for the passage of an injection liquid from the passage channel into a joint to be sealed.
The reliable and permanent seal of construction or expansion joints in structures, especially in concrete structures, presents a general problem. Due to the lack of space and traffic problems, construction is done increasingly underground, especially in densely populated areas. Typical examples are underground garages or underground streets. The reliable function and stability of these structures are largely dependent on their tightness with respect to penetrating water, and for this reason the majority of such structures currently are built of water-impermeable concrete. The concrete structure must ensure, in addition to its basic supporting and enveloping function, the function of satisfactory sealing. In so doing, the configuration and design of the construction and expansion joints thereof become important with regard to tightness and impermeability.
Conventional joint guarantees frequently do not fulfill the demands imposed on them, resulting in considerable costs for cleaning and/or repairing leaky joints or cracks. For this reason, injection hoses of the type specified in DE-OS 35 12 470, DE-OS 33 20 875 and DE-GM 84 25 518 were developed to be built into the construction joints and through which an injection liquid is injected into the joint region in order to ensure that it will be water-tight. The injection process employs an injection hose and occurs usually when the curing of the concrete and thus the relaxation behavior typical of such building material has terminated. The injection liquid is injected into a passage channel of a substantially water-impermeable base body of the injection hose, from which it can issue through exit openings into the vicinity of the joint. The exit openings are covered as shown in DE-OS 25 12 470 or by means of strips that are made of compressible material and that are embedded in depressions disposed on the outside of the base body. The injection hose is held together by means of a hose or covering that is made of a liquid-permeable material and that envelops the base body and the strips. Owing to the injection pressure, the strips are compressed and the joints between the depressions and the strips are expanded in such a manner that the injection liquid can issue from the injection hose. Then the injection liquid can be left to harden, resulting usually in the joint being sealed by means of the injection liquid that has issued from the injection hose. However, the injection liquid also hardens in the hose interior, and it is impossible to check the quality of the seal. If in the course of time the interior of the structure shifts and thus the imperviousness of the joint is lost or, for example, the concrete cracks due to an overload, it no longer is possible to again pressure grout into the joint or crack, since the joint or crack no longer is accessible with the injection hose. Occasionally, it also happens that during initial pressure grouting the joint had large cavities or leaks, into which or through which large amounts of injection material have escaped laterally. Due to resultant pressure loss, the injection material could not reach all such joint regions, and porosity of the joint remained. In such case also, with the known method of using injection hoses it is not possible to seal subsequently the joint and check the joint seal for completion.